ABSTRACT
Objective To explore the effect of HeLa cells infected with Coxsackie virus B3 (CVB3) on the changes of mTOR signal pathway under different nutritional conditions.Methods The HeLa cells were cultured under conventional culture and serum starvation culture.(1) For the conventional method,the medium with 10 g/L fetal bovine serum was added for 24 h after the Hela cells were fused into 40％ to 50％,and the medium was changed on the next day,then the virus group was infected with CVB3 of 50％ tissue culture infective dose (TCID50).However,the control group was cultured by 2 g/L fetal bovine serum.(2) For the serum starvation method,HeLa cells were cultured with the medium without fetal bovine serum for 24 h.Then the virus group was infected with CVB3 of TCID50.The cells in control group were cultured by 2 g/L fetal bovine serum.Cell morphology changes were observed by inverted microscope,and the expressions of the mTOR,p70S6K mRNA were detected with Real-time PCR at 3 h,6 h,9 h,12 h,24 h respectively in both conventional culture and serum starvation groups.Results The expressions of mTOR and p70S6K mRNA were lower in the virus group than those in control group at 12 h and the 24 h (all P ＜0.05) in the conventional culture group.And the expressions of mTOR and p70S6K mRNA in the virus group were lower than those in the control group at every time points (all P ＜ 0.05) in serum starvation group.The expressions of mTOR and p70S6K mRNA in group with serum starvation virus and the control groups were higher than those in conventional culture group in all time points,but only the expressions of mTOR mRNA were significantly different between the 2 groups (all P ＜0.05),however,the expressions of p70S6K mRNA had no significant difference between the 2 groups (all P ＞ 0.05).Conclusion CVB3 may be able to down-regulate the expressions of mTOR and p70S6K mRNA.